A region of volatile memory in a system that is used by secure software applications needs to be protected from malicious modifications by unauthorized entities. These malicious modifications, also referred to as “attacks” may be software attacks or hardware attacks. One method to provide confidentiality and integrity protection for secure software applications is to integrate a large volatile memory in the Central Processing Unit (CPU) or processor package, to be used as “private memory” by the secure software applications. However, the integration of a large volatile memory in the CPU package is expensive.
Thus, secure software applications are typically stored in external (that is, external to the CPU) memory. Memory regions (areas) in the external memory to store the secure software applications can be visible or invisible to the Operating System (OS) in the system. If these memory regions are visible to the OS, they need to be protected from software attacks and hardware attacks. If these memory regions are not visible to the OS (called “stolen memory areas”), and there is some access control mechanism, they need to be protected from hardware attacks, that is, from an attacker that has physical access to external memory.
Although the following Detailed Description will proceed with reference being made to illustrative embodiments of the claimed subject matter, many alternatives, modifications, and variations thereof will be apparent to those skilled in the art. Accordingly, it is intended that the claimed subject matter be viewed broadly, and be defined only as set forth in the accompanying claims.